A slut muffin is a term first coined in fall 2005 that describes a person who is appealing to the eye and is very charming. They can also be quite seductive.

A slut muffin is someone like Jim McMullen, Angelina Jolie, James Bond, etc. "As I heard him talk to those ladies at the party, there was no questioning his suave aura and the way his words escaped his mouth ever so smoothly. He was most certainly a slut muffin."

Slutmuffin is the compound of two words slut and muffin. May be used as a term of endearment between friends or lovers.
May be used as a compliment.
The female version of studmuffin.
Can be used to describe a woman who is outwardly very sweet, but has a very sexy side behind closed doors,
or someone who is outwardly both very sweet and very sexy.
Rarely used as an insult because of the cuteness of the term.

I love you my little slutmuffin.
Slutmuffin you are so sexy!
My girl is a total slutmuffin.
Did you see that slutmuffin? I'd totally tap that!
That Librarian is cute, I bet she is a total slutmuffin.